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1.
背腰部按摩对运动员免疫能力的影响   总被引:1,自引:0,他引:1  
运用对照法、机体实验法、生化测定法对运动员免疫能力进行研究。对16名长期大运动量训练运动员进行背腰部按摩,经运动员组和对照组的血液检测,比较两组免疫功能以及补体系统的指标。结果显示:对运动员背腰部按摩后,运动员组各项免疫功能与补体系统指标产生较大的变化;运动员的感冒和感染其它疾病次数减少;缩短恢复时间;增强抵抗疾病能力。结论:背腰部按摩能改善运动性免疫抑制现象、提高机体免疫能力、增强体质。  相似文献   
2.
本文以资源科学与地理科学、区域科学的理论交叉为依据,从论述县城资源科学内涵及其在区域资源─—经济系统中的地位与作用入手,对县域资源基本特征进行了分析与概括,可为县域资源开发利用提供参考。  相似文献   
3.
Objective: To observe the effect of Yangxueqingnao particles on rat vascular smooth muscle cell (VSMC) proliferation induced by lysophosphatidic acid (LPA). Methods: The amount of3H-TdR (3H-thymidine) admixed in cultured rat VSMC was measured and mitogen-activated protein kinase (MAPK) activity and lipid peroxidation end product malondialdehyde (MDA)content of the VSMC were assayed. Results: 1×10-9, 1×10-8, 1×10-7 mol/L LPA in a concentration dependent manner, induced the amount of 3H-TdR admixed, MAP kinase activity, and MDA content of the cultured rat VSMC to increase. However, 5%, 10%,and 15% Yangxueqingnao serum preincubation resulted in a decrease of 23.0%, 42.0%, and 52.0% (P<0.01) respectively in the amount of 3H-TdR admixed, a decline in VSMC MAP kinase activity of 13.9% (P<0.05), 29.6% (P<0.01), and 48.9% (P<0.01)respectively, and also, a decrease in MDA content of VSMC of 19.4%, 24.7%, and 43.2% (P<0.01) respectively, in the 1×10-7mol/L LPA-treated VSMC. Conclusions: LPA activates the proliferation and lipid peroxidation of VSMC in a concentration dependent manner. The LPA-induced VSMC proliferation is related to the activity of MAP kinases, enzymes involved in an intracellular signalling pathway. The results of the present study showed that Yangxueqingnao particles can effectively inhibit LPA-induced VSMC proliferation, MAP kinase activation, and reduce lipid peroxidative lesion.  相似文献   
4.
在最需要诚信的今天,缺失真诚、失信于人已成为国人无奈的日常话题,刘震云针对信息时代因为手机带来的信任危机和情感状态的困境,写出了迄今自认为最好的小说《手机》,实现了对自己文学创作的一种超越。作为《手机》的电影编剧,刘震云同时还根据文化消费市场的需要,先写电影剧本再写小说,并把小说与影片捆绑一起推向市场,作为一个“触电”极为成功的小说作家,实现了小说与电影、艺术与市场的双赢。  相似文献   
5.
手机文学亦称“短信文学”或“拇指文学”,是创作者为手机量身定做、给手机用户提供可阅读文本的文学样式。受手机平台的限制,手机文学作品篇幅短小。手机文学具有语言精炼含蓄、内蕴深厚、哲理性强的特点。它的出现,大大拓宽了文学的表现对象,也给更多的文学青年开辟出一块新的发表园地。  相似文献   
6.
The Hybrid Fiber-Coax (HFC) network is being paid close attention to in recent years as a bi-directional broadband access network. To achieve seamless connection with the backbone network, and Asynchronous Transfer Mode (ATM) Network Network Interface (NNI) cell format is used as the basic transmission packet unit in the HFC system. As the transmission condition of the HFC system’s upstream channel is bad, two improved header error control (HEC) schemes, i. e. the improved HEC and the cell interleaving technique, are employed to guarantee the packet integrity. Theoretical analysis of the results showed that the improved HEC and the cell interleaving technique are applicable to isolated random errors and burst errors, respectively.  相似文献   
7.
INTRODUCTIONATMhasgreatsuperiorityincertainaspects,suchasresourceallocationflexibility ,qualityofserviceguaranteeing ,integratedtrafficsupport ing ,etc .ATMhasbeenadoptedbyInternation alTelecommunicationUnion (ITU)astheex changeandmultiplexingtechniquesofth…  相似文献   
8.
Cell therapy in congestive heart failure   总被引:5,自引:0,他引:5  
Congestive heart failure (CHF) has emerged as a major worldwide epidemic and its main causes seem to be the aging of the population and the survival of patients with post-myocardial infarction. Cardiomyocyte dropout (necrosis and apoptosis) plays a critical role in the progress of CHF; thus treatment of CHF by exogenous cell implantation will be a promising medical approach. In the acute phase of cardiac damage cardiac stem cells (CSCs) within the heart divide symmetrically and/or asymmetrically in response to the change of heart homeostasis, and at the same time homing of bone marrow stem cells (BMCs) to injured area is thought to occur, which not only reconstitutes CSC population to normal levels but also repairs the heart by differentiation into cardiac tissue. So far, basic studies by using potential sources such as BMCs and CSCs to treat animat CHF have shown improved ventricular remodelling and heart function. Recently, however, a few of randomized, double-blind, placebo-controlled clinical trials demonstrated mixed results in heart failure with BMC therapy during acute myocardial infarction.  相似文献   
9.
The development of ovarian follicular cells is controlled by multiple circulating and local hormones and factors, including follicle-stimulating hormone (FSH) and epidermal growth factor (EGF). In this study, the stage-specific effect of EGF on FSH-induced proliferation of granulosa cells was evaluated in the ovarian follicles of egg-laying chickens. Results showed that EGF and its receptor (EGFR) mRNAs displayed a high expression in granulosa cells from the prehierarchical follicles, including the large white follicle (LWF) and small yellow follicle (SYF), and thereafter the expression decreased markedly to the stage of the largest preovulatory follicle. SYF represents a turning point of EGF/EGFR mRNA expression during follicle selection. Subsequently the granulosa cells from SYF were cultured to reveal the mediation of EGF in FSH action. Cell proliferation was remarkably increased by treatment with either EGF or FSH (0.1–100 ng/ml). This result was confirmed by elevated proliferating cell nuclear antigen (PCNA) expression and decreased cell apoptosis. Furthermore, EGF-induced cell proliferation was accompanied by increased mRNA expressions of EGFR, FSH receptor, and the cell cycle-regulating genes (cyclins D1 and E1, cyclin-dependent kinases 2 and 6) as well as decreased expression of luteinizing hormone receptor mRNA. However, the EGF or FSH-elicited effect was reversed by simultaneous treatment with an EGFR inhibitor AG1478. In conclusion, EGF and EGFR expressions manifested stage-specific changes during follicular development and EGF mediated FSH-induced cell proliferation and retarded cell differentiation in the prehierarchical follicles. These expressions thus stimulated follicular growth before selection in the egg-laying chicken.  相似文献   
10.
金叶日本冬青组培增殖技术研究   总被引:1,自引:0,他引:1  
以金叶日本冬青(Ilexcrenata)幼嫩茎段获得的无菌苗作外植体,通过在MS培养基中加入不同质量浓度的NAA和6-BA、选取茎段不同部位、设置液体培养基琼脂不同加量、不同pH值、不同光照强度等处理,分别对金叶日本冬青离体增殖培养进行研究,从而筛选增殖效果最佳的培养基配方。结果表明,1.0mg/L6-BA结合0.5mg/LNAA的增殖效果最佳;不同部位的外植体对增殖具有一定影响,试验发现采用茎尖培养,效果最佳;不同琼脂浓度、pH值及光照强度对其增殖均有一定影响,在生产中利用近似流体态的0.2%琼脂培养基效果较好;培养基pH值为6.0时效果最佳,芽数量多,苗生长健壮;在自然光培养下,芽增殖系数、苗高度和植株生长状况都优于相同光强的日光处理。  相似文献   
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